extensions/libxt_CLASSIFY.c

   1 /* Shared library add-on to iptables to add CLASSIFY target support. */
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include <stdlib.h>
   5 #include <getopt.h>
   6
   7 #include <xtables.h>
   8 #include <linux/netfilter/x_tables.h>
   9 #include <linux/netfilter/xt_CLASSIFY.h>
  10 #include <linux/types.h>
  11 #include <linux/pkt_sched.h>
  12
  13 static void
  14 CLASSIFY_help(void)
  15 {
  16         printf(
  17 "CLASSIFY target options:\n"
  18 "--set-class MAJOR:MINOR    Set skb->priority value (always hexadecimal!)\n");
  19 }
  20
  21 static const struct option CLASSIFY_opts[] = {
  22         { "set-class", 1, NULL, '1' },
  23         { .name = NULL }
  24 };
  25
  26 static int CLASSIFY_string_to_priority(const char *s, unsigned int *p)
  27 {
  28         unsigned int i, j;
  29
  30         if (sscanf(s, "%x:%x", &i, &j) != 2)
  31                 return 1;
  32
  33         *p = TC_H_MAKE(i<<16, j);
  34         return 0;
  35 }
  36
  37 static int
  38 CLASSIFY_parse(int c, char **argv, int invert, unsigned int *flags,
  39       const void *entry,
  40       struct xt_entry_target **target)
  41 {
  42         struct xt_classify_target_info *clinfo
  43                 = (struct xt_classify_target_info *)(*target)->data;
  44
  45         switch (c) {
  46         case '1':
  47                 if (CLASSIFY_string_to_priority(optarg, &clinfo->priority))
  48                         xtables_error(PARAMETER_PROBLEM,
  49                                    "Bad class value `%s'", optarg);
  50                 if (*flags)
  51                         xtables_error(PARAMETER_PROBLEM,
  52                                    "CLASSIFY: Can't specify --set-class twice");
  53                 *flags = 1;
  54                 break;
  55
  56         default:
  57                 return 0;
  58         }
  59
  60         return 1;
  61 }
  62
  63 static void
  64 CLASSIFY_final_check(unsigned int flags)
  65 {
  66         if (!flags)
  67                 xtables_error(PARAMETER_PROBLEM,
  68                            "CLASSIFY: Parameter --set-class is required");
  69 }
  70
  71 static void
  72 CLASSIFY_print_class(unsigned int priority, int numeric)
  73 {
  74         printf("%x:%x ", TC_H_MAJ(priority)>>16, TC_H_MIN(priority));
  75 }
  76
  77 static void
  78 CLASSIFY_print(const void *ip,
  79       const struct xt_entry_target *target,
  80       int numeric)
  81 {
  82         const struct xt_classify_target_info *clinfo =
  83                 (const struct xt_classify_target_info *)target->data;
  84         printf("CLASSIFY set ");
  85         CLASSIFY_print_class(clinfo->priority, numeric);
  86 }
  87
  88 static void
  89 CLASSIFY_save(const void *ip, const struct xt_entry_target *target)
  90 {
  91         const struct xt_classify_target_info *clinfo =
  92                 (const struct xt_classify_target_info *)target->data;
  93
  94         printf("--set-class %.4x:%.4x ",
  95                TC_H_MAJ(clinfo->priority)>>16, TC_H_MIN(clinfo->priority));
  96 }
  97
  98 static struct xtables_target classify_target = {
  99         .family         = NFPROTO_UNSPEC,
 100         .name           = "CLASSIFY",
 101         .version        = XTABLES_VERSION,
 102         .size           = XT_ALIGN(sizeof(struct xt_classify_target_info)),
 103         .userspacesize  = XT_ALIGN(sizeof(struct xt_classify_target_info)),
 104         .help           = CLASSIFY_help,
 105         .parse          = CLASSIFY_parse,
 106         .final_check    = CLASSIFY_final_check,
 107         .print          = CLASSIFY_print,
 108         .save           = CLASSIFY_save,
 109         .extra_opts     = CLASSIFY_opts,
 110 };
 111
 112 void _init(void)
 113 {
 114         xtables_register_target(&classify_target);
 115 }